ESPHome 2026.10: Faster ESP8266 Builds, Smaller OTA Updates, and Four Things to Check First

ESPHome 2026.10.0 went stable on October 21 after six betas. ESPHome's own count is "786 pull requests from over 60 contributors," which is a lot of change for something that runs inside your light switches and sensors.

Most of it is good news. Some of it will break a device if you update without reading. I'll do the breaking stuff first, because that's the part that costs you an evening.

Read this before you hit "Update all"

ESPHome's release post lists these in its quick-version summary. Four stood out to me as the ones most likely to catch a normal home setup:

1. Sendspin speakers need a newer Music Assistant. Sendspin connections are now encrypted, and the device needs Music Assistant 2.10.7 or 2.11.0b4 or newer. ESPHome's words: "update Music Assistant first, or the device will not connect." Order matters here. Music Assistant first, then the speaker.
2. Lights with initial_state: now actually use it at boot. That sounds like a fix, and it is. But if you set an initial_state years ago and forgot about it, your light will start honoring it after a power blip. Search your YAML for it.
3. codec_support_enabled on speaker media players "is gone." If it's in your config, validation will tell you. Remove it.
4. IR climate devices lose the combined heat/cool auto mode by default if they have supports_heat: false or supports_cool: false. If you built an IR remote for a cooling-only unit, the mode list in Home Assistant will look different.

None of these are hard to fix. They're just the kind of thing you don't connect to an update three days later when the porch light comes on at 2 a.m.

The ESP8266 change is the big one

ESPHome says "Roughly 40% of ESPHome devices run on ESP8266." Those are the cheap, older chips inside a lot of plugs and early DIY sensors. In 2026.10, the native ESP8266 Arduino toolchain is now the default build path instead of PlatformIO.

What that buys you, per ESPHome: it retires Rosetta on Apple Silicon Macs, and it cuts cold compile time "nearly in half." Their test, on an M5 Max with the same config: 9.2 seconds cold instead of 17.8. That's their machine and their config, so your numbers will differ. The direction is what matters. If you keep a drawer full of ESP8266 devices and recompile them every few months, this adds up.

The PlatformIO path still exists for now. It "warns on validation and goes away in 2027.4.0." So if you have a weird board that only builds on PlatformIO, you have until 2027.4.0 to sort it out. I wouldn't leave it to the last release.

Smaller OTA updates, especially on bad Wi-Fi

OTA uploads are now compressed on ESP32, RP2040, LibreTiny and host builds using a new deflate decoder. ESPHome says updates ship "about a third fewer bytes."

The more interesting number is on a lossy link. ESPHome measured an ESP32 at 15% simulated packet loss and saw upload times drop "from 317/113s to 74/67s." Everyone has that one device in the garage or the far bedroom that takes forever to flash. That's the device this helps.

Note what's not on that list: ESP8266.

New things worth playing with

Wi-Fi motion sensing with no sensor. The espectre component brings Wi-Fi Channel State Information (CSI) motion sensing to ESPHome. In ESPHome's words, "an ESP32 and an existing WiFi AP act as a motion detector without additional sensing hardware." I'd treat this as an experiment, not a replacement for a PIR or mmWave sensor in a room where an automation has to be right. It's still a neat trick for a board you probably already own.

Outgoing API connections. There's a new outgoing_connection option under api:, so the device opens the connection to Home Assistant itself instead of waiting to be reached. That should help when Home Assistant can't reach the device directly, say across a NAT or a separate network. It's "Noise only," which means it requires encryption:. Good. A device that dials out should be encrypted.

More Zigbee on ESP32. ESP32 Zigbee support gains measurement clusters, switches and numbers. If you've been watching ESPHome Zigbee from the sidelines, it's filling in.

A device-side Home Assistant onboarding wizard. It's in the release, but per ESPHome, "The wizard will not be shown until Home Assistant 2026.11." So you won't see it yet.

An MCP endpoint in Device Builder. The bundled Device Builder now has an optional endpoint that lets AI agents edit, validate, compile and flash configs. That one deserves its own write-up, and it has one.

How I'd update

My order of operations:

1. Read the full changelog for any component you use that I didn't mention. Seriously, 786 PRs.
2. Update Music Assistant first if you have Sendspin speakers.
3. Grep your configs for initial_state, codec_support_enabled, supports_heat and supports_cool.
4. Update one device of each type, check it in Home Assistant, then do the rest.

It's a good release. The ESP8266 speedup alone is worth it if you have a lot of them. Just don't update the whole fleet at 11 p.m. on a Sunday.